'Brad Pitt and George Clooney both fall in the red zone of the BMI chart.' Photograph: Denis Balibouse/Reuters

Forget summer, it's the first couple of weeks of January that constitute the journalistic year's silly season … if you are fat. The year 2013 has been no different: where once you might have written a resolution on the first page of your diary to eat fewer biscuits, Bridget Jones style, now new year's weight loss rhetoric has been amped up into the domain of thinktank press releases trying to prove they have something useful to contribute to the pressing problem of obesity.

A couple of reports have been cynically released and regurgitated in the last two days to cash in on the anxiety about bodies and consumption that descends like a cloud of fart around this time of year. The most recent, A Dose of Localism: The Role of Councils in Public Health, produced by the Local Government Information Unit (LGiU), would be funny if it weren't so rotten and expensively generated. Like others that came before, it surfs the tsunami of "fat panic" that has been drowning all in its path for the last 10 years or so.

The LGiU acknowledges that local governments are looking for cost-cutting measures as they assume responsibility for what looks set to be some pricey NHS service provision concerning diabetes, dementia and heart disease. As ever, it is social welfare that is the focus of cuts. The report's sponsors make the classic mistake that statistical correlation indicates causation in relation to both these health problems and obesity. Oh well, everybody else does it – so why be any different. With this in mind, the LGiU has come up with the stunning idea of withholding benefits from fat claimants who refuse to comply with sanctions (in the form of forced exercise).

A few simple questions reveal why this is an idiotic proposal: will there be scales at the jobcentre? Someone with a tape measure on hand when you go to sign on? Presumably Body Mass Index (BMI) will be the fallible tool that decides who gets sanctioned and who does not (let us not forget that Brad Pitt and George Clooney both fall in the red zone of the BMI chart). Who would decide what sort of exercise would be most appropriate? What is the evidence that exercise prevents dementia anyway? What if you did the exercise and still didn't get any thinner, or if the exercise exacerbated your existing health conditions? What if you're already a super-fit fat person on hard times? Give us answers, LGiU.

Why stop there? The report talks about "incentivising" people to exercise. It is hard to imagine more incentive to lose weight than the intense stigma, discrimination, street harassment and systemic social exclusion that fat people already face. If body weight was a choice solely mediated by eating less and exercising more, we would all have lost weight ages ago. Fat people are incentivised enough and take extraordinary risks to assume the bodies of "good", non-fat citizens. My friend is currently recuperating from gastric band surgery that has modified her body to malabsorb nourishment for the rest of her life. She has fought to be normatively thin at every stage of her 63 years, is more than willing to risk the inevitable miserable effects of such invasive treatment, and is not alone in this.

The way to improve fat people's wellbeing, which would also have the added benefit of improving people's health across the board, is not to treat weight loss as a panacea (it clearly does not work as a long-term remedy for health and social problems associated with fat). Instead, the LGiU should be developing health at every size interventions, fat activist communities and pioneering projects such as medical self-advocacy, anti-discrimination work and other low-cost, low-risk initiatives with proven track records. Improving people's access to good housing, meaningful work and a living wage wouldn't hurt either.

But LGiU's report is not about improving people's health. It is the kindly face of hatred, the result of mixing a loathing for poor people with the wider medically sanctioned disgust of fat in order to do things a bit more cheaply. Contrary to stereotypes of fat capitalists or fat cats so beloved by the left, fat people are more likely to be found in the more impoverished sections of society. The LGiU's proposals further entrench fat people within these quarters, punishing us for daring to exist, undermining our wellbeing and blaming us all along.

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